ABC News’ Robin Roberts talks to Mark Zuckerberg about the site’s new tool.

Conversations over the dinner table with his med-student girlfriend helped Mark Zuckerberg formulate his latest big idea — harnessing the power of Facebook to help eliminate the critical shortage of organs for patients desperately in need of life-saving transplants.

And it was his friendship with Apple founder Steve Jobs, whose life was extended by years following a liver transplant, in part, that spurred the 27-year-old Facebook founder and CEO to help put that idea into practice.

“Facebook is really about communicating and telling stories… We think that people can really help spread awareness of organ donation and that they want to participate in this to their friends. And that can be a big part of helping solve the crisis that’s out there,” Zuckerberg told ABC’s Robin Roberts in an exclusive interview at the company’s headquarters.